The polymerization of alpha-olefins by transition metal complexes, i.e. Ziegler-type catalysts, has been practiced since the 1950's. Over the years many support materials such as silica, alumina, Group IIA metal halides and hydroxy halides, have been used with Ziegler-type catalysts. However, catalysts containing these support materials require careful and extensive preparation procedures. Moreover, there is still a need for catalysts which are more active and which produce more highly stereo regular polymers.
The practice of the instant invention offers many advantages including: (1) the supports are derived from inexpensive and readily available minerals; (2) the preparation of the support requires only moderate conditions and unsophisticated equipment and techniques; (3) the application of the catalyst to the support is easily accomplished; (4) the required milling time is significantly reduced; (5) the catalysts produced herein are more active than prior art catalysts; (6) the inventive catalysts produce more highly stereo regular polymers than prior art catalysts; and (7) the instant catalysts are less sensitive to oxygen and water than prior art catalysts.